Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs...
[linux-2.6] / drivers / net / wireless / b43 / dma.c
1 /*
2
3   Broadcom B43 wireless driver
4
5   DMA ringbuffer and descriptor allocation/management
6
7   Copyright (c) 2005, 2006 Michael Buesch <mb@bu3sch.de>
8
9   Some code in this file is derived from the b44.c driver
10   Copyright (C) 2002 David S. Miller
11   Copyright (C) Pekka Pietikainen
12
13   This program is free software; you can redistribute it and/or modify
14   it under the terms of the GNU General Public License as published by
15   the Free Software Foundation; either version 2 of the License, or
16   (at your option) any later version.
17
18   This program is distributed in the hope that it will be useful,
19   but WITHOUT ANY WARRANTY; without even the implied warranty of
20   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
21   GNU General Public License for more details.
22
23   You should have received a copy of the GNU General Public License
24   along with this program; see the file COPYING.  If not, write to
25   the Free Software Foundation, Inc., 51 Franklin Steet, Fifth Floor,
26   Boston, MA 02110-1301, USA.
27
28 */
29
30 #include "b43.h"
31 #include "dma.h"
32 #include "main.h"
33 #include "debugfs.h"
34 #include "xmit.h"
35
36 #include <linux/dma-mapping.h>
37 #include <linux/pci.h>
38 #include <linux/delay.h>
39 #include <linux/skbuff.h>
40 #include <linux/etherdevice.h>
41 #include <asm/div64.h>
42
43
44 /* 32bit DMA ops. */
45 static
46 struct b43_dmadesc_generic *op32_idx2desc(struct b43_dmaring *ring,
47                                           int slot,
48                                           struct b43_dmadesc_meta **meta)
49 {
50         struct b43_dmadesc32 *desc;
51
52         *meta = &(ring->meta[slot]);
53         desc = ring->descbase;
54         desc = &(desc[slot]);
55
56         return (struct b43_dmadesc_generic *)desc;
57 }
58
59 static void op32_fill_descriptor(struct b43_dmaring *ring,
60                                  struct b43_dmadesc_generic *desc,
61                                  dma_addr_t dmaaddr, u16 bufsize,
62                                  int start, int end, int irq)
63 {
64         struct b43_dmadesc32 *descbase = ring->descbase;
65         int slot;
66         u32 ctl;
67         u32 addr;
68         u32 addrext;
69
70         slot = (int)(&(desc->dma32) - descbase);
71         B43_WARN_ON(!(slot >= 0 && slot < ring->nr_slots));
72
73         addr = (u32) (dmaaddr & ~SSB_DMA_TRANSLATION_MASK);
74         addrext = (u32) (dmaaddr & SSB_DMA_TRANSLATION_MASK)
75             >> SSB_DMA_TRANSLATION_SHIFT;
76         addr |= ssb_dma_translation(ring->dev->dev);
77         ctl = (bufsize - ring->frameoffset)
78             & B43_DMA32_DCTL_BYTECNT;
79         if (slot == ring->nr_slots - 1)
80                 ctl |= B43_DMA32_DCTL_DTABLEEND;
81         if (start)
82                 ctl |= B43_DMA32_DCTL_FRAMESTART;
83         if (end)
84                 ctl |= B43_DMA32_DCTL_FRAMEEND;
85         if (irq)
86                 ctl |= B43_DMA32_DCTL_IRQ;
87         ctl |= (addrext << B43_DMA32_DCTL_ADDREXT_SHIFT)
88             & B43_DMA32_DCTL_ADDREXT_MASK;
89
90         desc->dma32.control = cpu_to_le32(ctl);
91         desc->dma32.address = cpu_to_le32(addr);
92 }
93
94 static void op32_poke_tx(struct b43_dmaring *ring, int slot)
95 {
96         b43_dma_write(ring, B43_DMA32_TXINDEX,
97                       (u32) (slot * sizeof(struct b43_dmadesc32)));
98 }
99
100 static void op32_tx_suspend(struct b43_dmaring *ring)
101 {
102         b43_dma_write(ring, B43_DMA32_TXCTL, b43_dma_read(ring, B43_DMA32_TXCTL)
103                       | B43_DMA32_TXSUSPEND);
104 }
105
106 static void op32_tx_resume(struct b43_dmaring *ring)
107 {
108         b43_dma_write(ring, B43_DMA32_TXCTL, b43_dma_read(ring, B43_DMA32_TXCTL)
109                       & ~B43_DMA32_TXSUSPEND);
110 }
111
112 static int op32_get_current_rxslot(struct b43_dmaring *ring)
113 {
114         u32 val;
115
116         val = b43_dma_read(ring, B43_DMA32_RXSTATUS);
117         val &= B43_DMA32_RXDPTR;
118
119         return (val / sizeof(struct b43_dmadesc32));
120 }
121
122 static void op32_set_current_rxslot(struct b43_dmaring *ring, int slot)
123 {
124         b43_dma_write(ring, B43_DMA32_RXINDEX,
125                       (u32) (slot * sizeof(struct b43_dmadesc32)));
126 }
127
128 static const struct b43_dma_ops dma32_ops = {
129         .idx2desc = op32_idx2desc,
130         .fill_descriptor = op32_fill_descriptor,
131         .poke_tx = op32_poke_tx,
132         .tx_suspend = op32_tx_suspend,
133         .tx_resume = op32_tx_resume,
134         .get_current_rxslot = op32_get_current_rxslot,
135         .set_current_rxslot = op32_set_current_rxslot,
136 };
137
138 /* 64bit DMA ops. */
139 static
140 struct b43_dmadesc_generic *op64_idx2desc(struct b43_dmaring *ring,
141                                           int slot,
142                                           struct b43_dmadesc_meta **meta)
143 {
144         struct b43_dmadesc64 *desc;
145
146         *meta = &(ring->meta[slot]);
147         desc = ring->descbase;
148         desc = &(desc[slot]);
149
150         return (struct b43_dmadesc_generic *)desc;
151 }
152
153 static void op64_fill_descriptor(struct b43_dmaring *ring,
154                                  struct b43_dmadesc_generic *desc,
155                                  dma_addr_t dmaaddr, u16 bufsize,
156                                  int start, int end, int irq)
157 {
158         struct b43_dmadesc64 *descbase = ring->descbase;
159         int slot;
160         u32 ctl0 = 0, ctl1 = 0;
161         u32 addrlo, addrhi;
162         u32 addrext;
163
164         slot = (int)(&(desc->dma64) - descbase);
165         B43_WARN_ON(!(slot >= 0 && slot < ring->nr_slots));
166
167         addrlo = (u32) (dmaaddr & 0xFFFFFFFF);
168         addrhi = (((u64) dmaaddr >> 32) & ~SSB_DMA_TRANSLATION_MASK);
169         addrext = (((u64) dmaaddr >> 32) & SSB_DMA_TRANSLATION_MASK)
170             >> SSB_DMA_TRANSLATION_SHIFT;
171         addrhi |= (ssb_dma_translation(ring->dev->dev) << 1);
172         if (slot == ring->nr_slots - 1)
173                 ctl0 |= B43_DMA64_DCTL0_DTABLEEND;
174         if (start)
175                 ctl0 |= B43_DMA64_DCTL0_FRAMESTART;
176         if (end)
177                 ctl0 |= B43_DMA64_DCTL0_FRAMEEND;
178         if (irq)
179                 ctl0 |= B43_DMA64_DCTL0_IRQ;
180         ctl1 |= (bufsize - ring->frameoffset)
181             & B43_DMA64_DCTL1_BYTECNT;
182         ctl1 |= (addrext << B43_DMA64_DCTL1_ADDREXT_SHIFT)
183             & B43_DMA64_DCTL1_ADDREXT_MASK;
184
185         desc->dma64.control0 = cpu_to_le32(ctl0);
186         desc->dma64.control1 = cpu_to_le32(ctl1);
187         desc->dma64.address_low = cpu_to_le32(addrlo);
188         desc->dma64.address_high = cpu_to_le32(addrhi);
189 }
190
191 static void op64_poke_tx(struct b43_dmaring *ring, int slot)
192 {
193         b43_dma_write(ring, B43_DMA64_TXINDEX,
194                       (u32) (slot * sizeof(struct b43_dmadesc64)));
195 }
196
197 static void op64_tx_suspend(struct b43_dmaring *ring)
198 {
199         b43_dma_write(ring, B43_DMA64_TXCTL, b43_dma_read(ring, B43_DMA64_TXCTL)
200                       | B43_DMA64_TXSUSPEND);
201 }
202
203 static void op64_tx_resume(struct b43_dmaring *ring)
204 {
205         b43_dma_write(ring, B43_DMA64_TXCTL, b43_dma_read(ring, B43_DMA64_TXCTL)
206                       & ~B43_DMA64_TXSUSPEND);
207 }
208
209 static int op64_get_current_rxslot(struct b43_dmaring *ring)
210 {
211         u32 val;
212
213         val = b43_dma_read(ring, B43_DMA64_RXSTATUS);
214         val &= B43_DMA64_RXSTATDPTR;
215
216         return (val / sizeof(struct b43_dmadesc64));
217 }
218
219 static void op64_set_current_rxslot(struct b43_dmaring *ring, int slot)
220 {
221         b43_dma_write(ring, B43_DMA64_RXINDEX,
222                       (u32) (slot * sizeof(struct b43_dmadesc64)));
223 }
224
225 static const struct b43_dma_ops dma64_ops = {
226         .idx2desc = op64_idx2desc,
227         .fill_descriptor = op64_fill_descriptor,
228         .poke_tx = op64_poke_tx,
229         .tx_suspend = op64_tx_suspend,
230         .tx_resume = op64_tx_resume,
231         .get_current_rxslot = op64_get_current_rxslot,
232         .set_current_rxslot = op64_set_current_rxslot,
233 };
234
235 static inline int free_slots(struct b43_dmaring *ring)
236 {
237         return (ring->nr_slots - ring->used_slots);
238 }
239
240 static inline int next_slot(struct b43_dmaring *ring, int slot)
241 {
242         B43_WARN_ON(!(slot >= -1 && slot <= ring->nr_slots - 1));
243         if (slot == ring->nr_slots - 1)
244                 return 0;
245         return slot + 1;
246 }
247
248 static inline int prev_slot(struct b43_dmaring *ring, int slot)
249 {
250         B43_WARN_ON(!(slot >= 0 && slot <= ring->nr_slots - 1));
251         if (slot == 0)
252                 return ring->nr_slots - 1;
253         return slot - 1;
254 }
255
256 #ifdef CONFIG_B43_DEBUG
257 static void update_max_used_slots(struct b43_dmaring *ring,
258                                   int current_used_slots)
259 {
260         if (current_used_slots <= ring->max_used_slots)
261                 return;
262         ring->max_used_slots = current_used_slots;
263         if (b43_debug(ring->dev, B43_DBG_DMAVERBOSE)) {
264                 b43dbg(ring->dev->wl,
265                        "max_used_slots increased to %d on %s ring %d\n",
266                        ring->max_used_slots,
267                        ring->tx ? "TX" : "RX", ring->index);
268         }
269 }
270 #else
271 static inline
272     void update_max_used_slots(struct b43_dmaring *ring, int current_used_slots)
273 {
274 }
275 #endif /* DEBUG */
276
277 /* Request a slot for usage. */
278 static inline int request_slot(struct b43_dmaring *ring)
279 {
280         int slot;
281
282         B43_WARN_ON(!ring->tx);
283         B43_WARN_ON(ring->stopped);
284         B43_WARN_ON(free_slots(ring) == 0);
285
286         slot = next_slot(ring, ring->current_slot);
287         ring->current_slot = slot;
288         ring->used_slots++;
289
290         update_max_used_slots(ring, ring->used_slots);
291
292         return slot;
293 }
294
295 static u16 b43_dmacontroller_base(enum b43_dmatype type, int controller_idx)
296 {
297         static const u16 map64[] = {
298                 B43_MMIO_DMA64_BASE0,
299                 B43_MMIO_DMA64_BASE1,
300                 B43_MMIO_DMA64_BASE2,
301                 B43_MMIO_DMA64_BASE3,
302                 B43_MMIO_DMA64_BASE4,
303                 B43_MMIO_DMA64_BASE5,
304         };
305         static const u16 map32[] = {
306                 B43_MMIO_DMA32_BASE0,
307                 B43_MMIO_DMA32_BASE1,
308                 B43_MMIO_DMA32_BASE2,
309                 B43_MMIO_DMA32_BASE3,
310                 B43_MMIO_DMA32_BASE4,
311                 B43_MMIO_DMA32_BASE5,
312         };
313
314         if (type == B43_DMA_64BIT) {
315                 B43_WARN_ON(!(controller_idx >= 0 &&
316                               controller_idx < ARRAY_SIZE(map64)));
317                 return map64[controller_idx];
318         }
319         B43_WARN_ON(!(controller_idx >= 0 &&
320                       controller_idx < ARRAY_SIZE(map32)));
321         return map32[controller_idx];
322 }
323
324 static inline
325     dma_addr_t map_descbuffer(struct b43_dmaring *ring,
326                               unsigned char *buf, size_t len, int tx)
327 {
328         dma_addr_t dmaaddr;
329
330         if (tx) {
331                 dmaaddr = ssb_dma_map_single(ring->dev->dev,
332                                              buf, len, DMA_TO_DEVICE);
333         } else {
334                 dmaaddr = ssb_dma_map_single(ring->dev->dev,
335                                              buf, len, DMA_FROM_DEVICE);
336         }
337
338         return dmaaddr;
339 }
340
341 static inline
342     void unmap_descbuffer(struct b43_dmaring *ring,
343                           dma_addr_t addr, size_t len, int tx)
344 {
345         if (tx) {
346                 ssb_dma_unmap_single(ring->dev->dev,
347                                      addr, len, DMA_TO_DEVICE);
348         } else {
349                 ssb_dma_unmap_single(ring->dev->dev,
350                                      addr, len, DMA_FROM_DEVICE);
351         }
352 }
353
354 static inline
355     void sync_descbuffer_for_cpu(struct b43_dmaring *ring,
356                                  dma_addr_t addr, size_t len)
357 {
358         B43_WARN_ON(ring->tx);
359         ssb_dma_sync_single_for_cpu(ring->dev->dev,
360                                     addr, len, DMA_FROM_DEVICE);
361 }
362
363 static inline
364     void sync_descbuffer_for_device(struct b43_dmaring *ring,
365                                     dma_addr_t addr, size_t len)
366 {
367         B43_WARN_ON(ring->tx);
368         ssb_dma_sync_single_for_device(ring->dev->dev,
369                                        addr, len, DMA_FROM_DEVICE);
370 }
371
372 static inline
373     void free_descriptor_buffer(struct b43_dmaring *ring,
374                                 struct b43_dmadesc_meta *meta)
375 {
376         if (meta->skb) {
377                 dev_kfree_skb_any(meta->skb);
378                 meta->skb = NULL;
379         }
380 }
381
382 static int alloc_ringmemory(struct b43_dmaring *ring)
383 {
384         gfp_t flags = GFP_KERNEL;
385
386         /* The specs call for 4K buffers for 30- and 32-bit DMA with 4K
387          * alignment and 8K buffers for 64-bit DMA with 8K alignment. Testing
388          * has shown that 4K is sufficient for the latter as long as the buffer
389          * does not cross an 8K boundary.
390          *
391          * For unknown reasons - possibly a hardware error - the BCM4311 rev
392          * 02, which uses 64-bit DMA, needs the ring buffer in very low memory,
393          * which accounts for the GFP_DMA flag below.
394          *
395          * The flags here must match the flags in free_ringmemory below!
396          */
397         if (ring->type == B43_DMA_64BIT)
398                 flags |= GFP_DMA;
399         ring->descbase = ssb_dma_alloc_consistent(ring->dev->dev,
400                                                   B43_DMA_RINGMEMSIZE,
401                                                   &(ring->dmabase), flags);
402         if (!ring->descbase) {
403                 b43err(ring->dev->wl, "DMA ringmemory allocation failed\n");
404                 return -ENOMEM;
405         }
406         memset(ring->descbase, 0, B43_DMA_RINGMEMSIZE);
407
408         return 0;
409 }
410
411 static void free_ringmemory(struct b43_dmaring *ring)
412 {
413         gfp_t flags = GFP_KERNEL;
414
415         if (ring->type == B43_DMA_64BIT)
416                 flags |= GFP_DMA;
417
418         ssb_dma_free_consistent(ring->dev->dev, B43_DMA_RINGMEMSIZE,
419                                 ring->descbase, ring->dmabase, flags);
420 }
421
422 /* Reset the RX DMA channel */
423 static int b43_dmacontroller_rx_reset(struct b43_wldev *dev, u16 mmio_base,
424                                       enum b43_dmatype type)
425 {
426         int i;
427         u32 value;
428         u16 offset;
429
430         might_sleep();
431
432         offset = (type == B43_DMA_64BIT) ? B43_DMA64_RXCTL : B43_DMA32_RXCTL;
433         b43_write32(dev, mmio_base + offset, 0);
434         for (i = 0; i < 10; i++) {
435                 offset = (type == B43_DMA_64BIT) ? B43_DMA64_RXSTATUS :
436                                                    B43_DMA32_RXSTATUS;
437                 value = b43_read32(dev, mmio_base + offset);
438                 if (type == B43_DMA_64BIT) {
439                         value &= B43_DMA64_RXSTAT;
440                         if (value == B43_DMA64_RXSTAT_DISABLED) {
441                                 i = -1;
442                                 break;
443                         }
444                 } else {
445                         value &= B43_DMA32_RXSTATE;
446                         if (value == B43_DMA32_RXSTAT_DISABLED) {
447                                 i = -1;
448                                 break;
449                         }
450                 }
451                 msleep(1);
452         }
453         if (i != -1) {
454                 b43err(dev->wl, "DMA RX reset timed out\n");
455                 return -ENODEV;
456         }
457
458         return 0;
459 }
460
461 /* Reset the TX DMA channel */
462 static int b43_dmacontroller_tx_reset(struct b43_wldev *dev, u16 mmio_base,
463                                       enum b43_dmatype type)
464 {
465         int i;
466         u32 value;
467         u16 offset;
468
469         might_sleep();
470
471         for (i = 0; i < 10; i++) {
472                 offset = (type == B43_DMA_64BIT) ? B43_DMA64_TXSTATUS :
473                                                    B43_DMA32_TXSTATUS;
474                 value = b43_read32(dev, mmio_base + offset);
475                 if (type == B43_DMA_64BIT) {
476                         value &= B43_DMA64_TXSTAT;
477                         if (value == B43_DMA64_TXSTAT_DISABLED ||
478                             value == B43_DMA64_TXSTAT_IDLEWAIT ||
479                             value == B43_DMA64_TXSTAT_STOPPED)
480                                 break;
481                 } else {
482                         value &= B43_DMA32_TXSTATE;
483                         if (value == B43_DMA32_TXSTAT_DISABLED ||
484                             value == B43_DMA32_TXSTAT_IDLEWAIT ||
485                             value == B43_DMA32_TXSTAT_STOPPED)
486                                 break;
487                 }
488                 msleep(1);
489         }
490         offset = (type == B43_DMA_64BIT) ? B43_DMA64_TXCTL : B43_DMA32_TXCTL;
491         b43_write32(dev, mmio_base + offset, 0);
492         for (i = 0; i < 10; i++) {
493                 offset = (type == B43_DMA_64BIT) ? B43_DMA64_TXSTATUS :
494                                                    B43_DMA32_TXSTATUS;
495                 value = b43_read32(dev, mmio_base + offset);
496                 if (type == B43_DMA_64BIT) {
497                         value &= B43_DMA64_TXSTAT;
498                         if (value == B43_DMA64_TXSTAT_DISABLED) {
499                                 i = -1;
500                                 break;
501                         }
502                 } else {
503                         value &= B43_DMA32_TXSTATE;
504                         if (value == B43_DMA32_TXSTAT_DISABLED) {
505                                 i = -1;
506                                 break;
507                         }
508                 }
509                 msleep(1);
510         }
511         if (i != -1) {
512                 b43err(dev->wl, "DMA TX reset timed out\n");
513                 return -ENODEV;
514         }
515         /* ensure the reset is completed. */
516         msleep(1);
517
518         return 0;
519 }
520
521 /* Check if a DMA mapping address is invalid. */
522 static bool b43_dma_mapping_error(struct b43_dmaring *ring,
523                                   dma_addr_t addr,
524                                   size_t buffersize, bool dma_to_device)
525 {
526         if (unlikely(ssb_dma_mapping_error(ring->dev->dev, addr)))
527                 return 1;
528
529         switch (ring->type) {
530         case B43_DMA_30BIT:
531                 if ((u64)addr + buffersize > (1ULL << 30))
532                         goto address_error;
533                 break;
534         case B43_DMA_32BIT:
535                 if ((u64)addr + buffersize > (1ULL << 32))
536                         goto address_error;
537                 break;
538         case B43_DMA_64BIT:
539                 /* Currently we can't have addresses beyond
540                  * 64bit in the kernel. */
541                 break;
542         }
543
544         /* The address is OK. */
545         return 0;
546
547 address_error:
548         /* We can't support this address. Unmap it again. */
549         unmap_descbuffer(ring, addr, buffersize, dma_to_device);
550
551         return 1;
552 }
553
554 static int setup_rx_descbuffer(struct b43_dmaring *ring,
555                                struct b43_dmadesc_generic *desc,
556                                struct b43_dmadesc_meta *meta, gfp_t gfp_flags)
557 {
558         struct b43_rxhdr_fw4 *rxhdr;
559         dma_addr_t dmaaddr;
560         struct sk_buff *skb;
561
562         B43_WARN_ON(ring->tx);
563
564         skb = __dev_alloc_skb(ring->rx_buffersize, gfp_flags);
565         if (unlikely(!skb))
566                 return -ENOMEM;
567         dmaaddr = map_descbuffer(ring, skb->data, ring->rx_buffersize, 0);
568         if (b43_dma_mapping_error(ring, dmaaddr, ring->rx_buffersize, 0)) {
569                 /* ugh. try to realloc in zone_dma */
570                 gfp_flags |= GFP_DMA;
571
572                 dev_kfree_skb_any(skb);
573
574                 skb = __dev_alloc_skb(ring->rx_buffersize, gfp_flags);
575                 if (unlikely(!skb))
576                         return -ENOMEM;
577                 dmaaddr = map_descbuffer(ring, skb->data,
578                                          ring->rx_buffersize, 0);
579         }
580
581         if (b43_dma_mapping_error(ring, dmaaddr, ring->rx_buffersize, 0)) {
582                 b43err(ring->dev->wl, "RX DMA buffer allocation failed\n");
583                 dev_kfree_skb_any(skb);
584                 return -EIO;
585         }
586
587         meta->skb = skb;
588         meta->dmaaddr = dmaaddr;
589         ring->ops->fill_descriptor(ring, desc, dmaaddr,
590                                    ring->rx_buffersize, 0, 0, 0);
591
592         rxhdr = (struct b43_rxhdr_fw4 *)(skb->data);
593         rxhdr->frame_len = 0;
594
595         return 0;
596 }
597
598 /* Allocate the initial descbuffers.
599  * This is used for an RX ring only.
600  */
601 static int alloc_initial_descbuffers(struct b43_dmaring *ring)
602 {
603         int i, err = -ENOMEM;
604         struct b43_dmadesc_generic *desc;
605         struct b43_dmadesc_meta *meta;
606
607         for (i = 0; i < ring->nr_slots; i++) {
608                 desc = ring->ops->idx2desc(ring, i, &meta);
609
610                 err = setup_rx_descbuffer(ring, desc, meta, GFP_KERNEL);
611                 if (err) {
612                         b43err(ring->dev->wl,
613                                "Failed to allocate initial descbuffers\n");
614                         goto err_unwind;
615                 }
616         }
617         mb();
618         ring->used_slots = ring->nr_slots;
619         err = 0;
620       out:
621         return err;
622
623       err_unwind:
624         for (i--; i >= 0; i--) {
625                 desc = ring->ops->idx2desc(ring, i, &meta);
626
627                 unmap_descbuffer(ring, meta->dmaaddr, ring->rx_buffersize, 0);
628                 dev_kfree_skb(meta->skb);
629         }
630         goto out;
631 }
632
633 /* Do initial setup of the DMA controller.
634  * Reset the controller, write the ring busaddress
635  * and switch the "enable" bit on.
636  */
637 static int dmacontroller_setup(struct b43_dmaring *ring)
638 {
639         int err = 0;
640         u32 value;
641         u32 addrext;
642         u32 trans = ssb_dma_translation(ring->dev->dev);
643
644         if (ring->tx) {
645                 if (ring->type == B43_DMA_64BIT) {
646                         u64 ringbase = (u64) (ring->dmabase);
647
648                         addrext = ((ringbase >> 32) & SSB_DMA_TRANSLATION_MASK)
649                             >> SSB_DMA_TRANSLATION_SHIFT;
650                         value = B43_DMA64_TXENABLE;
651                         value |= (addrext << B43_DMA64_TXADDREXT_SHIFT)
652                             & B43_DMA64_TXADDREXT_MASK;
653                         b43_dma_write(ring, B43_DMA64_TXCTL, value);
654                         b43_dma_write(ring, B43_DMA64_TXRINGLO,
655                                       (ringbase & 0xFFFFFFFF));
656                         b43_dma_write(ring, B43_DMA64_TXRINGHI,
657                                       ((ringbase >> 32) &
658                                        ~SSB_DMA_TRANSLATION_MASK)
659                                       | (trans << 1));
660                 } else {
661                         u32 ringbase = (u32) (ring->dmabase);
662
663                         addrext = (ringbase & SSB_DMA_TRANSLATION_MASK)
664                             >> SSB_DMA_TRANSLATION_SHIFT;
665                         value = B43_DMA32_TXENABLE;
666                         value |= (addrext << B43_DMA32_TXADDREXT_SHIFT)
667                             & B43_DMA32_TXADDREXT_MASK;
668                         b43_dma_write(ring, B43_DMA32_TXCTL, value);
669                         b43_dma_write(ring, B43_DMA32_TXRING,
670                                       (ringbase & ~SSB_DMA_TRANSLATION_MASK)
671                                       | trans);
672                 }
673         } else {
674                 err = alloc_initial_descbuffers(ring);
675                 if (err)
676                         goto out;
677                 if (ring->type == B43_DMA_64BIT) {
678                         u64 ringbase = (u64) (ring->dmabase);
679
680                         addrext = ((ringbase >> 32) & SSB_DMA_TRANSLATION_MASK)
681                             >> SSB_DMA_TRANSLATION_SHIFT;
682                         value = (ring->frameoffset << B43_DMA64_RXFROFF_SHIFT);
683                         value |= B43_DMA64_RXENABLE;
684                         value |= (addrext << B43_DMA64_RXADDREXT_SHIFT)
685                             & B43_DMA64_RXADDREXT_MASK;
686                         b43_dma_write(ring, B43_DMA64_RXCTL, value);
687                         b43_dma_write(ring, B43_DMA64_RXRINGLO,
688                                       (ringbase & 0xFFFFFFFF));
689                         b43_dma_write(ring, B43_DMA64_RXRINGHI,
690                                       ((ringbase >> 32) &
691                                        ~SSB_DMA_TRANSLATION_MASK)
692                                       | (trans << 1));
693                         b43_dma_write(ring, B43_DMA64_RXINDEX, ring->nr_slots *
694                                       sizeof(struct b43_dmadesc64));
695                 } else {
696                         u32 ringbase = (u32) (ring->dmabase);
697
698                         addrext = (ringbase & SSB_DMA_TRANSLATION_MASK)
699                             >> SSB_DMA_TRANSLATION_SHIFT;
700                         value = (ring->frameoffset << B43_DMA32_RXFROFF_SHIFT);
701                         value |= B43_DMA32_RXENABLE;
702                         value |= (addrext << B43_DMA32_RXADDREXT_SHIFT)
703                             & B43_DMA32_RXADDREXT_MASK;
704                         b43_dma_write(ring, B43_DMA32_RXCTL, value);
705                         b43_dma_write(ring, B43_DMA32_RXRING,
706                                       (ringbase & ~SSB_DMA_TRANSLATION_MASK)
707                                       | trans);
708                         b43_dma_write(ring, B43_DMA32_RXINDEX, ring->nr_slots *
709                                       sizeof(struct b43_dmadesc32));
710                 }
711         }
712
713 out:
714         return err;
715 }
716
717 /* Shutdown the DMA controller. */
718 static void dmacontroller_cleanup(struct b43_dmaring *ring)
719 {
720         if (ring->tx) {
721                 b43_dmacontroller_tx_reset(ring->dev, ring->mmio_base,
722                                            ring->type);
723                 if (ring->type == B43_DMA_64BIT) {
724                         b43_dma_write(ring, B43_DMA64_TXRINGLO, 0);
725                         b43_dma_write(ring, B43_DMA64_TXRINGHI, 0);
726                 } else
727                         b43_dma_write(ring, B43_DMA32_TXRING, 0);
728         } else {
729                 b43_dmacontroller_rx_reset(ring->dev, ring->mmio_base,
730                                            ring->type);
731                 if (ring->type == B43_DMA_64BIT) {
732                         b43_dma_write(ring, B43_DMA64_RXRINGLO, 0);
733                         b43_dma_write(ring, B43_DMA64_RXRINGHI, 0);
734                 } else
735                         b43_dma_write(ring, B43_DMA32_RXRING, 0);
736         }
737 }
738
739 static void free_all_descbuffers(struct b43_dmaring *ring)
740 {
741         struct b43_dmadesc_generic *desc;
742         struct b43_dmadesc_meta *meta;
743         int i;
744
745         if (!ring->used_slots)
746                 return;
747         for (i = 0; i < ring->nr_slots; i++) {
748                 desc = ring->ops->idx2desc(ring, i, &meta);
749
750                 if (!meta->skb) {
751                         B43_WARN_ON(!ring->tx);
752                         continue;
753                 }
754                 if (ring->tx) {
755                         unmap_descbuffer(ring, meta->dmaaddr,
756                                          meta->skb->len, 1);
757                 } else {
758                         unmap_descbuffer(ring, meta->dmaaddr,
759                                          ring->rx_buffersize, 0);
760                 }
761                 free_descriptor_buffer(ring, meta);
762         }
763 }
764
765 static u64 supported_dma_mask(struct b43_wldev *dev)
766 {
767         u32 tmp;
768         u16 mmio_base;
769
770         tmp = b43_read32(dev, SSB_TMSHIGH);
771         if (tmp & SSB_TMSHIGH_DMA64)
772                 return DMA_64BIT_MASK;
773         mmio_base = b43_dmacontroller_base(0, 0);
774         b43_write32(dev, mmio_base + B43_DMA32_TXCTL, B43_DMA32_TXADDREXT_MASK);
775         tmp = b43_read32(dev, mmio_base + B43_DMA32_TXCTL);
776         if (tmp & B43_DMA32_TXADDREXT_MASK)
777                 return DMA_32BIT_MASK;
778
779         return DMA_30BIT_MASK;
780 }
781
782 static enum b43_dmatype dma_mask_to_engine_type(u64 dmamask)
783 {
784         if (dmamask == DMA_30BIT_MASK)
785                 return B43_DMA_30BIT;
786         if (dmamask == DMA_32BIT_MASK)
787                 return B43_DMA_32BIT;
788         if (dmamask == DMA_64BIT_MASK)
789                 return B43_DMA_64BIT;
790         B43_WARN_ON(1);
791         return B43_DMA_30BIT;
792 }
793
794 /* Main initialization function. */
795 static
796 struct b43_dmaring *b43_setup_dmaring(struct b43_wldev *dev,
797                                       int controller_index,
798                                       int for_tx,
799                                       enum b43_dmatype type)
800 {
801         struct b43_dmaring *ring;
802         int err;
803         dma_addr_t dma_test;
804
805         ring = kzalloc(sizeof(*ring), GFP_KERNEL);
806         if (!ring)
807                 goto out;
808
809         ring->nr_slots = B43_RXRING_SLOTS;
810         if (for_tx)
811                 ring->nr_slots = B43_TXRING_SLOTS;
812
813         ring->meta = kcalloc(ring->nr_slots, sizeof(struct b43_dmadesc_meta),
814                              GFP_KERNEL);
815         if (!ring->meta)
816                 goto err_kfree_ring;
817
818         ring->type = type;
819         ring->dev = dev;
820         ring->mmio_base = b43_dmacontroller_base(type, controller_index);
821         ring->index = controller_index;
822         if (type == B43_DMA_64BIT)
823                 ring->ops = &dma64_ops;
824         else
825                 ring->ops = &dma32_ops;
826         if (for_tx) {
827                 ring->tx = 1;
828                 ring->current_slot = -1;
829         } else {
830                 if (ring->index == 0) {
831                         ring->rx_buffersize = B43_DMA0_RX_BUFFERSIZE;
832                         ring->frameoffset = B43_DMA0_RX_FRAMEOFFSET;
833                 } else if (ring->index == 3) {
834                         ring->rx_buffersize = B43_DMA3_RX_BUFFERSIZE;
835                         ring->frameoffset = B43_DMA3_RX_FRAMEOFFSET;
836                 } else
837                         B43_WARN_ON(1);
838         }
839         spin_lock_init(&ring->lock);
840 #ifdef CONFIG_B43_DEBUG
841         ring->last_injected_overflow = jiffies;
842 #endif
843
844         if (for_tx) {
845                 ring->txhdr_cache = kcalloc(ring->nr_slots,
846                                             b43_txhdr_size(dev),
847                                             GFP_KERNEL);
848                 if (!ring->txhdr_cache)
849                         goto err_kfree_meta;
850
851                 /* test for ability to dma to txhdr_cache */
852                 dma_test = ssb_dma_map_single(dev->dev,
853                                               ring->txhdr_cache,
854                                               b43_txhdr_size(dev),
855                                               DMA_TO_DEVICE);
856
857                 if (b43_dma_mapping_error(ring, dma_test,
858                                           b43_txhdr_size(dev), 1)) {
859                         /* ugh realloc */
860                         kfree(ring->txhdr_cache);
861                         ring->txhdr_cache = kcalloc(ring->nr_slots,
862                                                     b43_txhdr_size(dev),
863                                                     GFP_KERNEL | GFP_DMA);
864                         if (!ring->txhdr_cache)
865                                 goto err_kfree_meta;
866
867                         dma_test = ssb_dma_map_single(dev->dev,
868                                                       ring->txhdr_cache,
869                                                       b43_txhdr_size(dev),
870                                                       DMA_TO_DEVICE);
871
872                         if (b43_dma_mapping_error(ring, dma_test,
873                                                   b43_txhdr_size(dev), 1)) {
874
875                                 b43err(dev->wl,
876                                        "TXHDR DMA allocation failed\n");
877                                 goto err_kfree_txhdr_cache;
878                         }
879                 }
880
881                 ssb_dma_unmap_single(dev->dev,
882                                      dma_test, b43_txhdr_size(dev),
883                                      DMA_TO_DEVICE);
884         }
885
886         err = alloc_ringmemory(ring);
887         if (err)
888                 goto err_kfree_txhdr_cache;
889         err = dmacontroller_setup(ring);
890         if (err)
891                 goto err_free_ringmemory;
892
893       out:
894         return ring;
895
896       err_free_ringmemory:
897         free_ringmemory(ring);
898       err_kfree_txhdr_cache:
899         kfree(ring->txhdr_cache);
900       err_kfree_meta:
901         kfree(ring->meta);
902       err_kfree_ring:
903         kfree(ring);
904         ring = NULL;
905         goto out;
906 }
907
908 #define divide(a, b)    ({      \
909         typeof(a) __a = a;      \
910         do_div(__a, b);         \
911         __a;                    \
912   })
913
914 #define modulo(a, b)    ({      \
915         typeof(a) __a = a;      \
916         do_div(__a, b);         \
917   })
918
919 /* Main cleanup function. */
920 static void b43_destroy_dmaring(struct b43_dmaring *ring,
921                                 const char *ringname)
922 {
923         if (!ring)
924                 return;
925
926 #ifdef CONFIG_B43_DEBUG
927         {
928                 /* Print some statistics. */
929                 u64 failed_packets = ring->nr_failed_tx_packets;
930                 u64 succeed_packets = ring->nr_succeed_tx_packets;
931                 u64 nr_packets = failed_packets + succeed_packets;
932                 u64 permille_failed = 0, average_tries = 0;
933
934                 if (nr_packets)
935                         permille_failed = divide(failed_packets * 1000, nr_packets);
936                 if (nr_packets)
937                         average_tries = divide(ring->nr_total_packet_tries * 100, nr_packets);
938
939                 b43dbg(ring->dev->wl, "DMA-%u %s: "
940                        "Used slots %d/%d, Failed frames %llu/%llu = %llu.%01llu%%, "
941                        "Average tries %llu.%02llu\n",
942                        (unsigned int)(ring->type), ringname,
943                        ring->max_used_slots,
944                        ring->nr_slots,
945                        (unsigned long long)failed_packets,
946                        (unsigned long long)nr_packets,
947                        (unsigned long long)divide(permille_failed, 10),
948                        (unsigned long long)modulo(permille_failed, 10),
949                        (unsigned long long)divide(average_tries, 100),
950                        (unsigned long long)modulo(average_tries, 100));
951         }
952 #endif /* DEBUG */
953
954         /* Device IRQs are disabled prior entering this function,
955          * so no need to take care of concurrency with rx handler stuff.
956          */
957         dmacontroller_cleanup(ring);
958         free_all_descbuffers(ring);
959         free_ringmemory(ring);
960
961         kfree(ring->txhdr_cache);
962         kfree(ring->meta);
963         kfree(ring);
964 }
965
966 #define destroy_ring(dma, ring) do {                            \
967         b43_destroy_dmaring((dma)->ring, __stringify(ring));    \
968         (dma)->ring = NULL;                                     \
969     } while (0)
970
971 void b43_dma_free(struct b43_wldev *dev)
972 {
973         struct b43_dma *dma;
974
975         if (b43_using_pio_transfers(dev))
976                 return;
977         dma = &dev->dma;
978
979         destroy_ring(dma, rx_ring);
980         destroy_ring(dma, tx_ring_AC_BK);
981         destroy_ring(dma, tx_ring_AC_BE);
982         destroy_ring(dma, tx_ring_AC_VI);
983         destroy_ring(dma, tx_ring_AC_VO);
984         destroy_ring(dma, tx_ring_mcast);
985 }
986
987 static int b43_dma_set_mask(struct b43_wldev *dev, u64 mask)
988 {
989         u64 orig_mask = mask;
990         bool fallback = 0;
991         int err;
992
993         /* Try to set the DMA mask. If it fails, try falling back to a
994          * lower mask, as we can always also support a lower one. */
995         while (1) {
996                 err = ssb_dma_set_mask(dev->dev, mask);
997                 if (!err)
998                         break;
999                 if (mask == DMA_64BIT_MASK) {
1000                         mask = DMA_32BIT_MASK;
1001                         fallback = 1;
1002                         continue;
1003                 }
1004                 if (mask == DMA_32BIT_MASK) {
1005                         mask = DMA_30BIT_MASK;
1006                         fallback = 1;
1007                         continue;
1008                 }
1009                 b43err(dev->wl, "The machine/kernel does not support "
1010                        "the required %u-bit DMA mask\n",
1011                        (unsigned int)dma_mask_to_engine_type(orig_mask));
1012                 return -EOPNOTSUPP;
1013         }
1014         if (fallback) {
1015                 b43info(dev->wl, "DMA mask fallback from %u-bit to %u-bit\n",
1016                         (unsigned int)dma_mask_to_engine_type(orig_mask),
1017                         (unsigned int)dma_mask_to_engine_type(mask));
1018         }
1019
1020         return 0;
1021 }
1022
1023 int b43_dma_init(struct b43_wldev *dev)
1024 {
1025         struct b43_dma *dma = &dev->dma;
1026         int err;
1027         u64 dmamask;
1028         enum b43_dmatype type;
1029
1030         dmamask = supported_dma_mask(dev);
1031         type = dma_mask_to_engine_type(dmamask);
1032         err = b43_dma_set_mask(dev, dmamask);
1033         if (err)
1034                 return err;
1035
1036         err = -ENOMEM;
1037         /* setup TX DMA channels. */
1038         dma->tx_ring_AC_BK = b43_setup_dmaring(dev, 0, 1, type);
1039         if (!dma->tx_ring_AC_BK)
1040                 goto out;
1041
1042         dma->tx_ring_AC_BE = b43_setup_dmaring(dev, 1, 1, type);
1043         if (!dma->tx_ring_AC_BE)
1044                 goto err_destroy_bk;
1045
1046         dma->tx_ring_AC_VI = b43_setup_dmaring(dev, 2, 1, type);
1047         if (!dma->tx_ring_AC_VI)
1048                 goto err_destroy_be;
1049
1050         dma->tx_ring_AC_VO = b43_setup_dmaring(dev, 3, 1, type);
1051         if (!dma->tx_ring_AC_VO)
1052                 goto err_destroy_vi;
1053
1054         dma->tx_ring_mcast = b43_setup_dmaring(dev, 4, 1, type);
1055         if (!dma->tx_ring_mcast)
1056                 goto err_destroy_vo;
1057
1058         /* setup RX DMA channel. */
1059         dma->rx_ring = b43_setup_dmaring(dev, 0, 0, type);
1060         if (!dma->rx_ring)
1061                 goto err_destroy_mcast;
1062
1063         /* No support for the TX status DMA ring. */
1064         B43_WARN_ON(dev->dev->id.revision < 5);
1065
1066         b43dbg(dev->wl, "%u-bit DMA initialized\n",
1067                (unsigned int)type);
1068         err = 0;
1069 out:
1070         return err;
1071
1072 err_destroy_mcast:
1073         destroy_ring(dma, tx_ring_mcast);
1074 err_destroy_vo:
1075         destroy_ring(dma, tx_ring_AC_VO);
1076 err_destroy_vi:
1077         destroy_ring(dma, tx_ring_AC_VI);
1078 err_destroy_be:
1079         destroy_ring(dma, tx_ring_AC_BE);
1080 err_destroy_bk:
1081         destroy_ring(dma, tx_ring_AC_BK);
1082         return err;
1083 }
1084
1085 /* Generate a cookie for the TX header. */
1086 static u16 generate_cookie(struct b43_dmaring *ring, int slot)
1087 {
1088         u16 cookie;
1089
1090         /* Use the upper 4 bits of the cookie as
1091          * DMA controller ID and store the slot number
1092          * in the lower 12 bits.
1093          * Note that the cookie must never be 0, as this
1094          * is a special value used in RX path.
1095          * It can also not be 0xFFFF because that is special
1096          * for multicast frames.
1097          */
1098         cookie = (((u16)ring->index + 1) << 12);
1099         B43_WARN_ON(slot & ~0x0FFF);
1100         cookie |= (u16)slot;
1101
1102         return cookie;
1103 }
1104
1105 /* Inspect a cookie and find out to which controller/slot it belongs. */
1106 static
1107 struct b43_dmaring *parse_cookie(struct b43_wldev *dev, u16 cookie, int *slot)
1108 {
1109         struct b43_dma *dma = &dev->dma;
1110         struct b43_dmaring *ring = NULL;
1111
1112         switch (cookie & 0xF000) {
1113         case 0x1000:
1114                 ring = dma->tx_ring_AC_BK;
1115                 break;
1116         case 0x2000:
1117                 ring = dma->tx_ring_AC_BE;
1118                 break;
1119         case 0x3000:
1120                 ring = dma->tx_ring_AC_VI;
1121                 break;
1122         case 0x4000:
1123                 ring = dma->tx_ring_AC_VO;
1124                 break;
1125         case 0x5000:
1126                 ring = dma->tx_ring_mcast;
1127                 break;
1128         default:
1129                 B43_WARN_ON(1);
1130         }
1131         *slot = (cookie & 0x0FFF);
1132         B43_WARN_ON(!(ring && *slot >= 0 && *slot < ring->nr_slots));
1133
1134         return ring;
1135 }
1136
1137 static int dma_tx_fragment(struct b43_dmaring *ring,
1138                            struct sk_buff *skb)
1139 {
1140         const struct b43_dma_ops *ops = ring->ops;
1141         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1142         u8 *header;
1143         int slot, old_top_slot, old_used_slots;
1144         int err;
1145         struct b43_dmadesc_generic *desc;
1146         struct b43_dmadesc_meta *meta;
1147         struct b43_dmadesc_meta *meta_hdr;
1148         struct sk_buff *bounce_skb;
1149         u16 cookie;
1150         size_t hdrsize = b43_txhdr_size(ring->dev);
1151
1152 #define SLOTS_PER_PACKET  2
1153
1154         old_top_slot = ring->current_slot;
1155         old_used_slots = ring->used_slots;
1156
1157         /* Get a slot for the header. */
1158         slot = request_slot(ring);
1159         desc = ops->idx2desc(ring, slot, &meta_hdr);
1160         memset(meta_hdr, 0, sizeof(*meta_hdr));
1161
1162         header = &(ring->txhdr_cache[slot * hdrsize]);
1163         cookie = generate_cookie(ring, slot);
1164         err = b43_generate_txhdr(ring->dev, header,
1165                                  skb->data, skb->len, info, cookie);
1166         if (unlikely(err)) {
1167                 ring->current_slot = old_top_slot;
1168                 ring->used_slots = old_used_slots;
1169                 return err;
1170         }
1171
1172         meta_hdr->dmaaddr = map_descbuffer(ring, (unsigned char *)header,
1173                                            hdrsize, 1);
1174         if (b43_dma_mapping_error(ring, meta_hdr->dmaaddr, hdrsize, 1)) {
1175                 ring->current_slot = old_top_slot;
1176                 ring->used_slots = old_used_slots;
1177                 return -EIO;
1178         }
1179         ops->fill_descriptor(ring, desc, meta_hdr->dmaaddr,
1180                              hdrsize, 1, 0, 0);
1181
1182         /* Get a slot for the payload. */
1183         slot = request_slot(ring);
1184         desc = ops->idx2desc(ring, slot, &meta);
1185         memset(meta, 0, sizeof(*meta));
1186
1187         meta->skb = skb;
1188         meta->is_last_fragment = 1;
1189
1190         meta->dmaaddr = map_descbuffer(ring, skb->data, skb->len, 1);
1191         /* create a bounce buffer in zone_dma on mapping failure. */
1192         if (b43_dma_mapping_error(ring, meta->dmaaddr, skb->len, 1)) {
1193                 bounce_skb = __dev_alloc_skb(skb->len, GFP_ATOMIC | GFP_DMA);
1194                 if (!bounce_skb) {
1195                         ring->current_slot = old_top_slot;
1196                         ring->used_slots = old_used_slots;
1197                         err = -ENOMEM;
1198                         goto out_unmap_hdr;
1199                 }
1200
1201                 memcpy(skb_put(bounce_skb, skb->len), skb->data, skb->len);
1202                 dev_kfree_skb_any(skb);
1203                 skb = bounce_skb;
1204                 meta->skb = skb;
1205                 meta->dmaaddr = map_descbuffer(ring, skb->data, skb->len, 1);
1206                 if (b43_dma_mapping_error(ring, meta->dmaaddr, skb->len, 1)) {
1207                         ring->current_slot = old_top_slot;
1208                         ring->used_slots = old_used_slots;
1209                         err = -EIO;
1210                         goto out_free_bounce;
1211                 }
1212         }
1213
1214         ops->fill_descriptor(ring, desc, meta->dmaaddr, skb->len, 0, 1, 1);
1215
1216         if (info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM) {
1217                 /* Tell the firmware about the cookie of the last
1218                  * mcast frame, so it can clear the more-data bit in it. */
1219                 b43_shm_write16(ring->dev, B43_SHM_SHARED,
1220                                 B43_SHM_SH_MCASTCOOKIE, cookie);
1221         }
1222         /* Now transfer the whole frame. */
1223         wmb();
1224         ops->poke_tx(ring, next_slot(ring, slot));
1225         return 0;
1226
1227 out_free_bounce:
1228         dev_kfree_skb_any(skb);
1229 out_unmap_hdr:
1230         unmap_descbuffer(ring, meta_hdr->dmaaddr,
1231                          hdrsize, 1);
1232         return err;
1233 }
1234
1235 static inline int should_inject_overflow(struct b43_dmaring *ring)
1236 {
1237 #ifdef CONFIG_B43_DEBUG
1238         if (unlikely(b43_debug(ring->dev, B43_DBG_DMAOVERFLOW))) {
1239                 /* Check if we should inject another ringbuffer overflow
1240                  * to test handling of this situation in the stack. */
1241                 unsigned long next_overflow;
1242
1243                 next_overflow = ring->last_injected_overflow + HZ;
1244                 if (time_after(jiffies, next_overflow)) {
1245                         ring->last_injected_overflow = jiffies;
1246                         b43dbg(ring->dev->wl,
1247                                "Injecting TX ring overflow on "
1248                                "DMA controller %d\n", ring->index);
1249                         return 1;
1250                 }
1251         }
1252 #endif /* CONFIG_B43_DEBUG */
1253         return 0;
1254 }
1255
1256 /* Static mapping of mac80211's queues (priorities) to b43 DMA rings. */
1257 static struct b43_dmaring * select_ring_by_priority(struct b43_wldev *dev,
1258                                                     u8 queue_prio)
1259 {
1260         struct b43_dmaring *ring;
1261
1262         if (b43_modparam_qos) {
1263                 /* 0 = highest priority */
1264                 switch (queue_prio) {
1265                 default:
1266                         B43_WARN_ON(1);
1267                         /* fallthrough */
1268                 case 0:
1269                         ring = dev->dma.tx_ring_AC_VO;
1270                         break;
1271                 case 1:
1272                         ring = dev->dma.tx_ring_AC_VI;
1273                         break;
1274                 case 2:
1275                         ring = dev->dma.tx_ring_AC_BE;
1276                         break;
1277                 case 3:
1278                         ring = dev->dma.tx_ring_AC_BK;
1279                         break;
1280                 }
1281         } else
1282                 ring = dev->dma.tx_ring_AC_BE;
1283
1284         return ring;
1285 }
1286
1287 int b43_dma_tx(struct b43_wldev *dev, struct sk_buff *skb)
1288 {
1289         struct b43_dmaring *ring;
1290         struct ieee80211_hdr *hdr;
1291         int err = 0;
1292         unsigned long flags;
1293         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1294
1295         hdr = (struct ieee80211_hdr *)skb->data;
1296         if (info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM) {
1297                 /* The multicast ring will be sent after the DTIM */
1298                 ring = dev->dma.tx_ring_mcast;
1299                 /* Set the more-data bit. Ucode will clear it on
1300                  * the last frame for us. */
1301                 hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
1302         } else {
1303                 /* Decide by priority where to put this frame. */
1304                 ring = select_ring_by_priority(
1305                         dev, skb_get_queue_mapping(skb));
1306         }
1307
1308         spin_lock_irqsave(&ring->lock, flags);
1309         B43_WARN_ON(!ring->tx);
1310         if (unlikely(free_slots(ring) < SLOTS_PER_PACKET)) {
1311                 b43warn(dev->wl, "DMA queue overflow\n");
1312                 err = -ENOSPC;
1313                 goto out_unlock;
1314         }
1315         /* Check if the queue was stopped in mac80211,
1316          * but we got called nevertheless.
1317          * That would be a mac80211 bug. */
1318         B43_WARN_ON(ring->stopped);
1319
1320         /* Assign the queue number to the ring (if not already done before)
1321          * so TX status handling can use it. The queue to ring mapping is
1322          * static, so we don't need to store it per frame. */
1323         ring->queue_prio = skb_get_queue_mapping(skb);
1324
1325         err = dma_tx_fragment(ring, skb);
1326         if (unlikely(err == -ENOKEY)) {
1327                 /* Drop this packet, as we don't have the encryption key
1328                  * anymore and must not transmit it unencrypted. */
1329                 dev_kfree_skb_any(skb);
1330                 err = 0;
1331                 goto out_unlock;
1332         }
1333         if (unlikely(err)) {
1334                 b43err(dev->wl, "DMA tx mapping failure\n");
1335                 goto out_unlock;
1336         }
1337         ring->nr_tx_packets++;
1338         if ((free_slots(ring) < SLOTS_PER_PACKET) ||
1339             should_inject_overflow(ring)) {
1340                 /* This TX ring is full. */
1341                 ieee80211_stop_queue(dev->wl->hw, skb_get_queue_mapping(skb));
1342                 ring->stopped = 1;
1343                 if (b43_debug(dev, B43_DBG_DMAVERBOSE)) {
1344                         b43dbg(dev->wl, "Stopped TX ring %d\n", ring->index);
1345                 }
1346         }
1347 out_unlock:
1348         spin_unlock_irqrestore(&ring->lock, flags);
1349
1350         return err;
1351 }
1352
1353 /* Called with IRQs disabled. */
1354 void b43_dma_handle_txstatus(struct b43_wldev *dev,
1355                              const struct b43_txstatus *status)
1356 {
1357         const struct b43_dma_ops *ops;
1358         struct b43_dmaring *ring;
1359         struct b43_dmadesc_generic *desc;
1360         struct b43_dmadesc_meta *meta;
1361         int slot;
1362         bool frame_succeed;
1363
1364         ring = parse_cookie(dev, status->cookie, &slot);
1365         if (unlikely(!ring))
1366                 return;
1367
1368         spin_lock(&ring->lock); /* IRQs are already disabled. */
1369
1370         B43_WARN_ON(!ring->tx);
1371         ops = ring->ops;
1372         while (1) {
1373                 B43_WARN_ON(!(slot >= 0 && slot < ring->nr_slots));
1374                 desc = ops->idx2desc(ring, slot, &meta);
1375
1376                 if (meta->skb)
1377                         unmap_descbuffer(ring, meta->dmaaddr, meta->skb->len,
1378                                          1);
1379                 else
1380                         unmap_descbuffer(ring, meta->dmaaddr,
1381                                          b43_txhdr_size(dev), 1);
1382
1383                 if (meta->is_last_fragment) {
1384                         struct ieee80211_tx_info *info;
1385
1386                         BUG_ON(!meta->skb);
1387
1388                         info = IEEE80211_SKB_CB(meta->skb);
1389
1390                         /*
1391                          * Call back to inform the ieee80211 subsystem about
1392                          * the status of the transmission.
1393                          */
1394                         frame_succeed = b43_fill_txstatus_report(dev, info, status);
1395 #ifdef CONFIG_B43_DEBUG
1396                         if (frame_succeed)
1397                                 ring->nr_succeed_tx_packets++;
1398                         else
1399                                 ring->nr_failed_tx_packets++;
1400                         ring->nr_total_packet_tries += status->frame_count;
1401 #endif /* DEBUG */
1402                         ieee80211_tx_status_irqsafe(dev->wl->hw, meta->skb);
1403
1404                         /* skb is freed by ieee80211_tx_status_irqsafe() */
1405                         meta->skb = NULL;
1406                 } else {
1407                         /* No need to call free_descriptor_buffer here, as
1408                          * this is only the txhdr, which is not allocated.
1409                          */
1410                         B43_WARN_ON(meta->skb);
1411                 }
1412
1413                 /* Everything unmapped and free'd. So it's not used anymore. */
1414                 ring->used_slots--;
1415
1416                 if (meta->is_last_fragment)
1417                         break;
1418                 slot = next_slot(ring, slot);
1419         }
1420         dev->stats.last_tx = jiffies;
1421         if (ring->stopped) {
1422                 B43_WARN_ON(free_slots(ring) < SLOTS_PER_PACKET);
1423                 ieee80211_wake_queue(dev->wl->hw, ring->queue_prio);
1424                 ring->stopped = 0;
1425                 if (b43_debug(dev, B43_DBG_DMAVERBOSE)) {
1426                         b43dbg(dev->wl, "Woke up TX ring %d\n", ring->index);
1427                 }
1428         }
1429
1430         spin_unlock(&ring->lock);
1431 }
1432
1433 void b43_dma_get_tx_stats(struct b43_wldev *dev,
1434                           struct ieee80211_tx_queue_stats *stats)
1435 {
1436         const int nr_queues = dev->wl->hw->queues;
1437         struct b43_dmaring *ring;
1438         unsigned long flags;
1439         int i;
1440
1441         for (i = 0; i < nr_queues; i++) {
1442                 ring = select_ring_by_priority(dev, i);
1443
1444                 spin_lock_irqsave(&ring->lock, flags);
1445                 stats[i].len = ring->used_slots / SLOTS_PER_PACKET;
1446                 stats[i].limit = ring->nr_slots / SLOTS_PER_PACKET;
1447                 stats[i].count = ring->nr_tx_packets;
1448                 spin_unlock_irqrestore(&ring->lock, flags);
1449         }
1450 }
1451
1452 static void dma_rx(struct b43_dmaring *ring, int *slot)
1453 {
1454         const struct b43_dma_ops *ops = ring->ops;
1455         struct b43_dmadesc_generic *desc;
1456         struct b43_dmadesc_meta *meta;
1457         struct b43_rxhdr_fw4 *rxhdr;
1458         struct sk_buff *skb;
1459         u16 len;
1460         int err;
1461         dma_addr_t dmaaddr;
1462
1463         desc = ops->idx2desc(ring, *slot, &meta);
1464
1465         sync_descbuffer_for_cpu(ring, meta->dmaaddr, ring->rx_buffersize);
1466         skb = meta->skb;
1467
1468         rxhdr = (struct b43_rxhdr_fw4 *)skb->data;
1469         len = le16_to_cpu(rxhdr->frame_len);
1470         if (len == 0) {
1471                 int i = 0;
1472
1473                 do {
1474                         udelay(2);
1475                         barrier();
1476                         len = le16_to_cpu(rxhdr->frame_len);
1477                 } while (len == 0 && i++ < 5);
1478                 if (unlikely(len == 0)) {
1479                         /* recycle the descriptor buffer. */
1480                         sync_descbuffer_for_device(ring, meta->dmaaddr,
1481                                                    ring->rx_buffersize);
1482                         goto drop;
1483                 }
1484         }
1485         if (unlikely(len > ring->rx_buffersize)) {
1486                 /* The data did not fit into one descriptor buffer
1487                  * and is split over multiple buffers.
1488                  * This should never happen, as we try to allocate buffers
1489                  * big enough. So simply ignore this packet.
1490                  */
1491                 int cnt = 0;
1492                 s32 tmp = len;
1493
1494                 while (1) {
1495                         desc = ops->idx2desc(ring, *slot, &meta);
1496                         /* recycle the descriptor buffer. */
1497                         sync_descbuffer_for_device(ring, meta->dmaaddr,
1498                                                    ring->rx_buffersize);
1499                         *slot = next_slot(ring, *slot);
1500                         cnt++;
1501                         tmp -= ring->rx_buffersize;
1502                         if (tmp <= 0)
1503                                 break;
1504                 }
1505                 b43err(ring->dev->wl, "DMA RX buffer too small "
1506                        "(len: %u, buffer: %u, nr-dropped: %d)\n",
1507                        len, ring->rx_buffersize, cnt);
1508                 goto drop;
1509         }
1510
1511         dmaaddr = meta->dmaaddr;
1512         err = setup_rx_descbuffer(ring, desc, meta, GFP_ATOMIC);
1513         if (unlikely(err)) {
1514                 b43dbg(ring->dev->wl, "DMA RX: setup_rx_descbuffer() failed\n");
1515                 sync_descbuffer_for_device(ring, dmaaddr, ring->rx_buffersize);
1516                 goto drop;
1517         }
1518
1519         unmap_descbuffer(ring, dmaaddr, ring->rx_buffersize, 0);
1520         skb_put(skb, len + ring->frameoffset);
1521         skb_pull(skb, ring->frameoffset);
1522
1523         b43_rx(ring->dev, skb, rxhdr);
1524 drop:
1525         return;
1526 }
1527
1528 void b43_dma_rx(struct b43_dmaring *ring)
1529 {
1530         const struct b43_dma_ops *ops = ring->ops;
1531         int slot, current_slot;
1532         int used_slots = 0;
1533
1534         B43_WARN_ON(ring->tx);
1535         current_slot = ops->get_current_rxslot(ring);
1536         B43_WARN_ON(!(current_slot >= 0 && current_slot < ring->nr_slots));
1537
1538         slot = ring->current_slot;
1539         for (; slot != current_slot; slot = next_slot(ring, slot)) {
1540                 dma_rx(ring, &slot);
1541                 update_max_used_slots(ring, ++used_slots);
1542         }
1543         ops->set_current_rxslot(ring, slot);
1544         ring->current_slot = slot;
1545 }
1546
1547 static void b43_dma_tx_suspend_ring(struct b43_dmaring *ring)
1548 {
1549         unsigned long flags;
1550
1551         spin_lock_irqsave(&ring->lock, flags);
1552         B43_WARN_ON(!ring->tx);
1553         ring->ops->tx_suspend(ring);
1554         spin_unlock_irqrestore(&ring->lock, flags);
1555 }
1556
1557 static void b43_dma_tx_resume_ring(struct b43_dmaring *ring)
1558 {
1559         unsigned long flags;
1560
1561         spin_lock_irqsave(&ring->lock, flags);
1562         B43_WARN_ON(!ring->tx);
1563         ring->ops->tx_resume(ring);
1564         spin_unlock_irqrestore(&ring->lock, flags);
1565 }
1566
1567 void b43_dma_tx_suspend(struct b43_wldev *dev)
1568 {
1569         b43_power_saving_ctl_bits(dev, B43_PS_AWAKE);
1570         b43_dma_tx_suspend_ring(dev->dma.tx_ring_AC_BK);
1571         b43_dma_tx_suspend_ring(dev->dma.tx_ring_AC_BE);
1572         b43_dma_tx_suspend_ring(dev->dma.tx_ring_AC_VI);
1573         b43_dma_tx_suspend_ring(dev->dma.tx_ring_AC_VO);
1574         b43_dma_tx_suspend_ring(dev->dma.tx_ring_mcast);
1575 }
1576
1577 void b43_dma_tx_resume(struct b43_wldev *dev)
1578 {
1579         b43_dma_tx_resume_ring(dev->dma.tx_ring_mcast);
1580         b43_dma_tx_resume_ring(dev->dma.tx_ring_AC_VO);
1581         b43_dma_tx_resume_ring(dev->dma.tx_ring_AC_VI);
1582         b43_dma_tx_resume_ring(dev->dma.tx_ring_AC_BE);
1583         b43_dma_tx_resume_ring(dev->dma.tx_ring_AC_BK);
1584         b43_power_saving_ctl_bits(dev, 0);
1585 }
1586
1587 #ifdef CONFIG_B43_PIO
1588 static void direct_fifo_rx(struct b43_wldev *dev, enum b43_dmatype type,
1589                            u16 mmio_base, bool enable)
1590 {
1591         u32 ctl;
1592
1593         if (type == B43_DMA_64BIT) {
1594                 ctl = b43_read32(dev, mmio_base + B43_DMA64_RXCTL);
1595                 ctl &= ~B43_DMA64_RXDIRECTFIFO;
1596                 if (enable)
1597                         ctl |= B43_DMA64_RXDIRECTFIFO;
1598                 b43_write32(dev, mmio_base + B43_DMA64_RXCTL, ctl);
1599         } else {
1600                 ctl = b43_read32(dev, mmio_base + B43_DMA32_RXCTL);
1601                 ctl &= ~B43_DMA32_RXDIRECTFIFO;
1602                 if (enable)
1603                         ctl |= B43_DMA32_RXDIRECTFIFO;
1604                 b43_write32(dev, mmio_base + B43_DMA32_RXCTL, ctl);
1605         }
1606 }
1607
1608 /* Enable/Disable Direct FIFO Receive Mode (PIO) on a RX engine.
1609  * This is called from PIO code, so DMA structures are not available. */
1610 void b43_dma_direct_fifo_rx(struct b43_wldev *dev,
1611                             unsigned int engine_index, bool enable)
1612 {
1613         enum b43_dmatype type;
1614         u16 mmio_base;
1615
1616         type = dma_mask_to_engine_type(supported_dma_mask(dev));
1617
1618         mmio_base = b43_dmacontroller_base(type, engine_index);
1619         direct_fifo_rx(dev, type, mmio_base, enable);
1620 }
1621 #endif /* CONFIG_B43_PIO */